import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.UnknownHostException;

public class testClass {

	double[] ext = {
		20,
		18,
		21,
		25,
		22,
		18,
		20
	};
	
	public testClass() {
		
		for(int i = 1; i < ext.length-1; i++) {
			ext[i] = (ext[i] - ext[i-1]) + ext[i]; 
			System.out.println(ext[i]);
		};
		
	};
	
	public void test() {};
	
	public void test1() {};
	
	public static void main(String[] args) {
		
		testClass t = new testClass();
		
		
		
		
		 
		
		
//		String hostname = args[0];
//		int portnumber = Integer.parseInt(args[1]);
//		String userInput, serverInput;
//		Socket socket;
//		PrintWriter out;
//		BufferedReader in, stdIn;
//		boolean connection = true;
//		while (connection) {
//
//			try {
//				socket = new Socket();
//				socket.connect(new InetSocketAddress("localhost", 7789));
//				out = new PrintWriter(socket.getOutputStream(), true);
//				in = new BufferedReader(new InputStreamReader(
//						socket.getInputStream()));
//				stdIn = new BufferedReader(new InputStreamReader(System.in));
//				
//				while ((serverInput = in.readLine()) != null) {		
//					for(int i = 0; i <5; i++){
//						out.println("");
//					}
//					System.out.println(serverInput);
//					
//					if((userInput = stdIn.readLine()) != null){
//						out.println(userInput);
//					}
//
//				} 
//			} catch (UnknownHostException e) {
//				System.err.println("Don't know about host ");
//				System.exit(1);
//			} catch (IOException e) {
//				System.err.println("Couldn't get I/O for the connection to ");
//				System.exit(1);
//			} finally {
//
//			}
//		}

	}
}
